LIFE OF TERTIAEY PEETOD 239 



vertical thickness of more than a mile. ... At the present 

 time this ancient lake-basin, now 6000 to 8000 feet above the sea, 

 shows evidence of a vast erosion, and probabl}^ more than one-half 

 of the deposits once left in it have been washed away, mainly by 

 the action of the Colorado River. What remains forms one of 

 the most picturesque regions in the whole West, veritable mauvaises 

 terres, or bad lands, where slow denudation has carved out cliffs, 

 peaks, and columns of the most fantastic shapes and colours. This 

 same action has brought to light the remains of many extinct 

 animals, and the bones of the Dinocerata, from their great size, 

 naturally first attract the attention of the explorer." 



As regards the mental powers of these strange animals, Pro- 

 fessor Marsh saj's: 



" The brain-cavity of the Uintatherium is perhaps the most re- 

 markable feature in this remarkable genus. It shows us that the 

 brain was proportionately smaller than in any other known mam- 

 mal, recent or fossil, and even less than in some reptiles. It is, in 

 fact, the most reptilian brain in any known mammal. In U. mira- 

 bile (one of the large- tusked, horned species) it could apparently 

 have been drawn through the neural canal of all the presacral 

 vertebrae." "^ 



It was, in fact, a small oval mass of about the same diameter 

 as the spinal cord ! 



One other strange form which may belong to the earliest 

 ungulates has been found in the Upper Eocene of Egypt, and 

 forms a new suborder, Barjpoda. It is known from a very 

 complete skull (Fig. 76), which is remarkable for the very 

 regular set of teeth, as well as for the wonderful horn-cores, 

 two small at the back and two enormous ones projecting in 

 front. The skull is nearly 3 feet long, and the larger horn- 

 cores about 2% feet ; and as these certainly carried true horns 

 they probably surpassed any of the Dinocerata. Large quan- 

 tities of detached bones have also been obtained, sufficient to 

 show that the creature was an ungulate of elephantine dimen- 

 sions and altogether unique in appearance. This creature hail 

 a somewhat larsjer brain thnn the great American ungulates, 



